motor not charging battery

[Willie J]

I have a rebuilt 1995 70 HP Yamaha outboard. The motor runs finek, but only produces about 12 - 12.5 volts to the battery, rather than the 14 or so I expect. I replaced the regulator to no avail. My service guys claims all is well, but the battery loses charge time after time. -- New battery, too. What else should I check?

 

[99yam40]

Re: motor not charging battery

test the lighting coil like your service manual states
Ohms and peak voltages at different RPMs to see if in spec

 

[yamatech43]

Re: motor not charging battery/edited post

Re: motor not charging battery/edited post

Wait, have you had a problem with battery actually going down? Or is it so charged the rectifier/regulator doesn't want to send any juice to it....what are you reading the volts with(gauge on dash or real meter at leads)? If with
dash voltmeter, don't do that....may be more like 13.1 or so with meter, wish i knew if your battery had given
you a problem or you just noticed the voltage being 'low' for charging.....Edit: now i see another post saying batt. is actually going down....probably as stated in answer previous to my post. good luck.